For me, the quickest reload is a new gun. I dont have to be out of ammo to use my pistol. For me drawing my pistol is quicker than dropping and reloading a new mag.

Also, for a pistol, I find I use it more when Im sitting in the bush. If I am in a camping position its easier for me to swing my pistol around than attempt to swing around with my m4. Im not a huge fan of highcaps, they have their place though.